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Physical Review A

Down-conversion of a single photon with unit efficiency

Kazuki Koshino

Published Jan 6, 2009• 27 citations
Publisher

Abstract

The down-conversion dynamics of a single photon in a single three-level system are investigated theoretically. The wave functions of the output photons are obtained analytically as functions of the input photon profile, and the down-conversion probability is evaluated from these output wave functions. It is demonstrated that down-conversion of a single photon with unit efficiency is possible and the necessary conditions are clarified.

DOI
10.1103/physreva.79.013804

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The down-conversion dynamics of a single photon in a single three-level system are investigated theoretically. The wave functions of the output photons are obtained analytically as functions of the input photon profile, and the down-conversion probability is evaluated from these output wave functions. It is demonstrated that down-conversion of a single photon with unit efficiency is possible and the necessary conditions are clarified.
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We analyze the up conversion of a two-photon pulse having temporal entanglement on the basis of a full quantum formalism that treats both photons and optical media quantum mechanically. We derive a formula of the up-converted photon wave function, which is applicable to arbitrary input two-photon states for a three-level system, as the simplest second-order nonlinear optical system. As the input, we employ three kinds of temporally entangled two-photon pulses: correlated, uncorrelated, and anticorrelated. We observe the up-conversion efficiency and the temporal profile of the up-converted photon. Our results reveal the crossover behavior of the up conversion from anticorrelation to correlation and show how the temporal correlation in the input is reflected in the up-conversion process.
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